See also:

Automatic Operation
AUTO (Automatic): When automatic operation is active, the system controls the inside temperature, the air delivery, and the fan speed. Use the steps below to place the entire system in automatic mode ...

Automatic Operation
AUTO (Automatic): The system automatically controls the inside temperature, the air delivery, and the fan speed. To use automatic mode: 1. Press the AUTO button. When AUTO is selected, the current ...

Cooling System
If the vehicle has the Duramax® Diesel engine, see the Duramax® Diesel Supplement for more information. The cooling system allows the engine to maintain the correct working temperature. 5.3 L En ...